This invention relates to a stepless speed change device capable of changing its transmission speed and particularly suitable for use in a bicycle.
Such a kind of speed change device has been proposed, for example, as disclosed in Japanese Patent Application Publication No. 1,722/59.
In the prior art, however, a driving mechanism by pawls is arranged only in a single row, so that the number of the pawls available is limited, with the result that a cyclist is afflicted with pulsations in transmission.
With the prior art, moreover, shocks in transmission occur when the pawls taking part in transmission are switched. This results from a fact that there is a gap between tooth ends of a driving ratchet and a driven pawl which are about to take part in transmission, owing to difference in speed between them.